column_1 ASC,
column_2 DESC;
column_1 与 column_2 如果后面不指定排序规则,默认为 ASC 升序,以上语句按 column_1 升序,column_2 降序读取,等价如下语句:
SELECT
select_list
table
ORDER BY
column_1,
column_2 DESC;
假设 COMPANY 表有以下记录:
ID NAME AGE ADDRESS SALARY
---------- ---------- ---------- ---------- ----------
1 Paul 32 California 20000.0
2 Allen 25 Texas 15000.0
3 Teddy 23 Norway 20000.0
4 Mark 25 Rich-Mond 65000.0
5 David 27 Texas 85000.0
6 Kim 22 South-Hall 45000.0
7 James 24 Houston 10000.0
下面是一个实例,它会将结果按 SALARY 升序排序:
sqlite> SELECT * FROM COMPANY ORDER BY SALARY ASC;
这将产生以下结果:
ID NAME AGE ADDRESS SALARY
---------- ---------- ---------- ---------- ----------
7 James 24 Houston 10000.0
2 Allen 25 Texas 15000.0
1 Paul 32 California 20000.0
3 Teddy 23 Norway 20000.0
6 Kim 22 South-Hall 45000.0
4 Mark 25 Rich-Mond 65000.0
5 David 27 Texas 85000.0
下面是一个实例,它会将结果按 NAME 和 SALARY 升序排序:
sqlite> SELECT * FROM COMPANY ORDER BY NAME, SALARY ASC;
这将产生以下结果:
ID NAME AGE ADDRESS SALARY
---------- ---------- ---------- ---------- ----------
2 Allen 25 Texas 15000.0
5 David 27 Texas 85000.0
7 James 24 Houston 10000.0
6 Kim 22 South-Hall 45000.0
4 Mark 25 Rich-Mond 65000.0
1 Paul 32 California 20000.0
3 Teddy 23 Norway 20000.0
下面是一个实例,它会将结果按 NAME 降序排序:
sqlite> SELECT * FROM COMPANY ORDER BY NAME DESC;
这将产生以下结果:
ID NAME AGE ADDRESS SALARY
---------- ---------- ---------- ---------- ----------
3 Teddy 23 Norway 20000.0
1 Paul 32 California 20000.0
4 Mark 25 Rich-Mond 65000.0
6 Kim 22 South-Hall 45000.0
7 James 24 Houston 10000.0
5 David 27 Texas 85000.0
2 Allen 25 Texas 15000.0
select * from company order by salary,name desc;
id name age address salary
---------- ---------- ---------- ---------- ----------
7 James 24 Houston 10000.0
2 Allen 25 Texas 15000.0
3 Scy 30 Beijng 20000.0
1 Paul 32 Califonia 20000.0
6 Kim 22 South-Hall 45000.0
4 Mark 25 Rich-Mond 65000.0
5 David 27 Texas 85000.0
-
上面的排序优先按照salary降序排列
-
排序中有两个salary值相同的 id分别是3和1
-
然后这两条记录再按照name字段降序排列
总结:
有多个排序字段时,优先按照前面的排序,如果前面的排序中有值相同的,后面的字段才起作用,在这些值相同的记录中,按照后续字段排序!